All experimenters know that human and animal subjects do not respond uniformly to experimental treatments. Yet theories and findings in experimental psychology either ignore this causal effect heterogeneity or treat it as uninteresting error. This is the case even when data are available to examine effect heterogeneity directly, in within-subjects designs where experimental effects can be examined subject by subject. Using data from four repeated-measures experiments, we show that effect heterogeneity can be modeled readily, that its discovery presents exciting opportunities for theory and methods, and that allowing for it in study designs is good research practice. This evidence suggests that experimenters should work from the assumption that causal effects are heterogeneous. Such a working assumption will be of particular benefit, given the increasing diversity of subject populations in psychology.

Many everyday conversations, whether between close partners or strangers interacting for the first time, are about the world external to their relationship, such as music, food, or current events. Yet, the focus of most research on interpersonal relationships to date has been on the ways in which partners perceive each other and their relationship. We propose that one critical aspect of interpersonal interactions is developing a sense of dyadic, generalized shared reality—the subjective experience of sharing a set of inner states (e.g., thoughts, feelings, or beliefs) in common with a particular interaction partner about the world in general, including the world external to the relationship. Across 9 studies, we use mixed methods to investigate the unique role of generalized shared reality in interpersonal interactions, both between close partners and strangers. We hypothesize that generalized shared reality predicts how people connect with each other and perceive the world around them. We also investigate the observable, dyadic behavioral signatures of generalized shared reality in interpersonal interactions. Finally, we examine the motivation to uphold an existing sense of generalized shared reality. We hypothesize that couples high on baseline generalized shared reality exhibit motivated, dyadic interaction behaviors to reaffirm their generalized shared reality in the face of experimentally manipulated threat. By identifying a unique dimension of everyday interactions, these studies aim to capture a critical aspect of the lived subjective experience of human relationships that has not been captured before.

Social relationships can be a vital source of help in difficult times. However, attempts to provide social support that is visible—direct and recognized by recipients as help—can sometimes have unintended negative effects. By contrast, invisible support—provided indirectly such that recipients do not interpret the behavior as help—can circumvent potential negative effects. In this article, we synthesize empirical evidence on support visibility using three organizing questions: How do support attempts differ in visibility? Why is invisible support often more beneficial than visible support? When is invisible support, as opposed to visible support, needed? The answers to these questions can illuminate mechanisms of effective support generally, help explain known variability in support outcomes, and stimulate further research.

Social support can sometimes have negative consequences for recipients. One way of circumventing these negative effects is to provide support in an 'invisible' or indirect manner, such that recipients do not construe the behavior as a supportive act. However, little is known about how recipients' motivational states influence when visible (direct) support or invisible support is more beneficial. Using the framework of Regulatory Mode Theory, we predicted that recipients motivated to engage in critical evaluation (i.e., those with a predominant assessment motivation) would find invisible support more beneficial than visible support, whereas recipients motivated to initiate action (i.e., those with a predominant locomotion motivation) would find visible support more beneficial than invisible support. Findings from one 2 × 2 experiment (Study 1), two laboratory experiments (Studies 2-3), one dyadic study involving support conversations between friends (Study 4), and a meta-analysis aggregating data from all four studies supported these hypotheses. As predicted, support outcomes were better for assessment predominant recipients following invisible support, but were better for locomotion predominant recipients following visible support. Results indicate that support attempts could be made more effective by considering both support visibility and recipient motivation. (PsycINFO Database Record

Receiving social support can entail both costs and benefits for recipients. Thus, theories of effective support have proposed that support should address recipients' needs to be beneficial. This paper proposes the importance of support that addresses recipients' self-regulatory needs. We present a novel construct-regulatory effectiveness of support (RES)-which posits that support that addresses recipients' needs to understand their situation (truth) and to feel capable of managing their situation (control) will engender support benefits. We hypothesized that receiving support higher on RES would predict beneficial support outcomes. We further hypothesized that these effects would be especially pronounced for self-regulation relevant outcomes, such as better mood and increased motivation, which, in turn, can be important for successful self-regulation. We established the construct validity of RES and then investigated its effects in daily life and in laboratory support discussions. In 8 studies and a meta-analysis pooling across studies, results showed that RES predicted self-regulation relevant support outcomes, and these effects of RES were stronger than the effects of perceived responsiveness, a construct that is known to enhance interpersonal relationships. Furthermore, RES was linked to self-regulatory success: Participants who received support higher on RES were more motivated to perform well on a stressful speech, which subsequently predicted better speech performance. These findings enhance knowledge of effective social support by underscoring the importance of addressing recipients' self-regulatory needs in the support process.